Recently, with remarkable development of electronics and communication engineering, mobile communication terminals have various functions and mobile communication systems provide various services. That is, with rapid development of radio communication and data processing techniques, people can be offered with voice communication service, and furthermore, internet access, video communication, moving image message transmit services, etc. using mobile communication terminals. As mobile communication terminals spread rapidly, a considerable amount of human communication is made through the mobile communication terminals, and the mobile communication terminals became an indispensable communication means in modern society.
Mobile communication systems offering such mobile communication services include a mobile switching center (MSC), a home location register (HLR), a base station controller or radio network controller (BSC, RNC), a base transceiver station (BTS, Node B) and a mobile station (MS). The mobile switching center is an essential network element in a mobile communication network, and controls voice communication and various supplementary services, sets communication channels, and provides connection to various equipments and external network, etc. That is, the mobile switching center provides mobile communication subscribers a circuit switching service and a communication channel switching function.
Here, the home location register is linked with the switching center, and serves to manage and support mobility of mobile communication terminals. The home location register always knows the current location of mobile communication terminals through location registration. The mobile switching center provides location data of the mobile communication terminals to the home location register, and if necessary, may receive location data of the terminals from the home location register. For this purpose, the mobile switching center has a visitor location register, and stores temporarily and utilizes location data and subscriber data of mobile communication terminals under its control.
Thus, when there is a change in subscriber data, a subscriber data management server transmits the changed data to the home location register so that the change can be reflected on subscriber data stored in the home location register. Then, when there is a change in the subscriber data stored in the home location register, the home location register transmits the changed data to a mobile switching center where a corresponding subscriber's mobile communication terminal is under control so that the changed subscriber data can be reflected on a visitor location register provided in the switching center.
However, as the mobile communication systems become more complicated and the number of mobile communication subscribers increases year after year, an error in location registration often occurs, such as abnormal location registration, double location registration, etc. If such error is not corrected, it may have difficulty in normally transmitting the changed subscriber data to a switching center so that the changed subscriber data is reflected on the switching center.
Conventionally, to correct the error in location registration (failure to insert subscriber data) such as double location registration, abnormal location registration, etc., a message requesting a new location registration was transmitted to all switching centers recorded in or linked with a home location register.
However, this conventional solution enables all switching centers to perform a location registration whenever an error in location registration occurs. This leads to simultaneous location registration of a huge number of mobile switching centers, resulting in system overload.
In particular, the system overload intensively occurs to the home location register, and as a result, the home location register is beyond normal operation, for example, MAP failure. If so, a fatal problem may be raised that desired services cannot be provided to mobile communication subscribers well.